Current psychosocial interventions in autism generally target only specific aspects of social knowledge or functioning. Moreover, promising initial gains often fail to maintain or generalize. Our goal is to address the need for the development of interventions for older children and adolescents with autism spectrum disorders (ASD) in an innovative community-service model. Our treatment combines several well-documented behavioral strategies grouped into three categories (peers, play and performance) shown to have support in past social interventions. The proposal extends promising pilot findings of the SENSE Theatre approach - a synthesis of behavioral approaches with theatrical techniques delivered in a supportive peer-mediated program. Previous studies have shown improvement in social interaction skills and reduced stress. The proposed project will extend the findings using a randomized between-group experiment to more carefully assess whether previously detected changes in social interaction and stress responsivity are due to the treatment and the extent to which these changes generalize and maintain. These questions will be addressed in children and youth with ASD 8 to 16 years. The measurement protocol will assess the acquisition of social interaction skills measured by familiar (therapist, parent, peer) and unfamiliar (blind raters, other peers) informants across proximal (assessment, theatre) and distal (home, playground, school) contexts. Additionally, neuropsychological measures of social cognition/perception will be administered. Finally, we will measure change in social stress responsivity via observational (behavioral coding) and other-report (parental and self) measures. If expected findings are confirmed, this project will provide empirical support for the utilization of peer models in a community-based treatment that has generalized and maintained effects on a set of core deficits that otherwise have life-long consequences for children with ASD.